Portable electronic transceivers, such as cellular and cordless telephones, pagers and the like, are becoming increasingly popular. In some instances it is possible to send complete messages, including alpha-numerics and/or graphics by way of novel devices. Thus, complete messages can be sent to specific recipients by way of a pager, or the like, and upon receiving the complete message, the recipient may wish to transmit a response. In these instances it is desirable to have an electronic transmitting device of some sort included within the portable device. In other instances it may be desirable to share with others the message received, and/or simply receive and/or transmit communication data to additional electronic devices. The problem is that it is difficult and unwieldy to carry various communication transceivers and electronic devices, e.g. telephones and/or two-way radios, as well as pagers, remote controls and other devices.
In many instances it is desirable to provide a visual display on a communication transceiver to supply the operator with a visual message or graphical image. The problem is that the visual displays on prior art communications receivers are extremely limited in size, require relatively high electrical power as well as a great amount of area to be sufficiently large to produce a useful display, and in most instances are intended to be viewed by the operator of the device. In addition, and as previously stated, at times it is desirable for the image transmitted to the electronic transceiver to be viewable by more than just the user of the device. It is in this instance that a display capable of being viewed by many individuals is desired, such as a projection display.
In the prior art, it is common to provide visual displays utilizing liquid crystal displays, directly viewed light emitting diodes, etc. These produce very large and cumbersome displays that greatly increase the size of the transceiver and require relatively large amounts of power. Further, such displays, when used on portable electronic devices, such as pagers, cellular telephones, or the like, greatly limit the amount of message that can be received.
In one instance, the prior art includes a scanning mirror to produce a visual display but again this requires relatively large amounts of power and is very complicated and sensitive to shock. Also, the scanning mirror causes vibration in the unit that substantially reduces visual comfort and acceptability.
One way to alleviate the problem of size in visual displays and the inclusion of a projection display and/or data communication link into portable devices of this type is to utilize an electro-optical package incorporating a dual light source, namely one containing both LED light sources and vertical cavity surface emitting laser (VCSELs) light sources. By incorporating these two types of light sources within a single package, a visual display, such as a miniature virtual display generated by the LEDs and a projection display and/or data communication link generated by the VCSELs is possible.
Accordingly, a portable transceiver device that could receive communications and/or data, viewable through a visual display, such as a miniature virtual display, and receive and/or transmit data through a data interface port, such as an infra-red or visible data transmission interface and/or visible laser projection display would be highly advantageous. In achieving the design of such a transceiver, it would be advantageous to fabricate a dual sided light source that has formed thereon a common substrate, composed of a single semiconductor wafer, or a plurality of bonded semiconductor wafers, a plurality of visible LEDs and at least one vertical cavity surface emitting laser (VCSEL) fabricated to emit light in a visible range and/or an infra-red range. Therefore, desired is an integrated electro-optical package which has contained therein, a dual sided display chip mounted between either a pair of optically transparent mounting structures or mounted within a molded plastic base structure having defined therein central openings or windows formed on opposed surfaces of the structure, both types of mounting structures incorporating a means for interfacing with a printed circuit board and drive circuits, such as through, patterned electrical interconnects, connection/mounting pads, embedded lead frames and/or plated through-hole vias and optical elements.
Thus, there is a need for interconnect and packaging structures and techniques in which LED arrays, vertical cavity surface emitting lasers (VCSELs), optical elements and electronic circuitry can be conveniently incorporated
There is also a need for interconnect and packaging structures and techniques which can substantially reduce the limitation on size of the electro-optical package.
Therefore, it is a purpose of the present invention to provide a new and improved electro-optical package that includes a dual sided light source, or display chip.
It is a purpose of the present invention to provide for an integrated electro-optical package which is substantially smaller than previous integrated packages.
It is a purpose of the present invention to provide for an integrated electro-optical package in which an LED array, and at least one vertical cavity surface emitting laser (VCSEL) can be formed as a dual sided opto-electronic device, including electrical interconnects.
It is also a purpose of this invention to provide a package incorporating a novel method of fabricating a two-dimensional LED array and at least one vertical cavity surface emitting laser (VCSEL) on a single substrate, composed of one or more semiconductor wafers, thereby forming a dual sided display chip, having formed therein electrical interconnects, that in combination with optical elements, provides for high density information image manifestation apparatus applications, data communications transmission link applications, and projection display applications.